Apparatus for measuring the audience of a media presentation, such as a television program, are well-known in the industry. Knowledge of the size and composition of audiences to a television or radio broadcast is of paramount importance for the whole broadcast industry in order to get a clear idea of media consumer patterns, for use for example to rate the advertising space included in broadcasts.
Knowledge of the demographical composition of the audience is important for advertisers to optimize the effectiveness of their commercial messages by targeting the right groups for their products. It is also useful for program scheduling purposes for broadcasters.
In order to collect such information, usually a plurality of media consumers is enlisted for cooperating in an audience measurement survey for a predefined length of time. The group of viewers cooperating in the survey is called a panel, while each viewer participating in the panel is called a panel member.
Audience metering apparatus are then coupled to the media rendering devices of various types or display systems (hereinafter referred to as television sets or TV sets by way of example) used by panel members for watching television broadcasts at their respective viewing locations. Such metering apparatus (hereinafter referred to as meters) usually have at least two main goals: (a) determining the content choices made by consumers; and (b) registering the presence of one or more panel members (so that the exposure to the content can be accounted to produce audience data).
Knowledge of the distribution platform or peripheral device from which users make their media choices is also of critical importance to understand the way consumers interact with their TV devices and for advertisers to optimize the allocation of advertising space among the available platforms. Information about platform and/or device usage is deemed essential information by many markets around the world, and will be referred to herein as source information.
Audience metering apparatus have traditionally taken the form of a set-top box to be placed on top of or close to the monitored TV set or other media presentation device and wired to it and to all peripheral devices associated therewith. The data generated by such wired audience metering systems is usually deemed accurate and complete. In some variants of audience measurement solutions, viewers are required to identify themselves by declaring their presence in front of the monitored TV set, usually by pressing an identification key on a remote control to produce presence information (a concept known as a people meter system). A display is generally used to communicate different types of messages to the panel members, the most important one being the acknowledgement that the declaration procedure has been successfully completed.
In FIG. 1 an example is given of a typical prior art set-top metering device that is wire connected to a TV set under measurement.
Several detection methods have been used or attempted for electronic measurement of audiences, some based on indirect inference of the content by measuring a physical variable associated with it using wire connected set-top boxes, for example, measuring the frequency of an analog tuner to deduce the identity of a TV signal. Others are based on information directly associated with the content, for example, reading ancillary codes or correlating signatures produced from the broadcast signal.
Most conventional meters use a plurality of methods to cover as many measurement cases as possible. For example, a meter may use frequency measurement for signal identification in certain analog platforms, while using video matching techniques for other digital platforms where frequency reading alone cannot identify the signal chosen. In such cases, the available methods are switched in or out by the meter or system software according to the active device, i.e. what media distribution platform is in use at any given time. The detection methods may be active all the time. However, the meter must decide when such information is relevant and therefore should be logged. For example, in a given monitored TV setup, a frequency measurement probe may give an indication as long as the measured device is turned on (since the tuner's oscillator is always active), although that platform may not be in use most of the time; therefore the frequency indication must be qualified by source information in order to become meaningful.
The TARIS 5000 meter used by TNS is an example of a multi-method meter that uses a plurality of content determination techniques, each of them applicable in different situations. In summary, the TARIS 5000 meter uses audio-matching for signal identification. It makes particular use of enhanced audio matching (EAM) wherein station recognition is performed based on the soundtrack accompanying an image displayed on a television screen at a given time. In order to achieve this, all potential audio sources for the television set or other device being monitored must be connected to the TARIS 5000 meter. This involves the use of multiple output cables between peripheral devices, the television set, and the meter device itself via an audio breakout box (ABB) which is responsible for identifying the source of an audio signal and transmitting such information to the TARIS 5000 meter.
Known metering devices that make use of a plurality of different methods for signal identification need to determine first the source of the signal, as explained in the SKO document referenced above, so that the metering device can determine which method should be used in each case. Therefore, most prior art metering systems that report platform information are based on a two phase process by which the source or platform in use of the signal is identified as a first phase, so that then one or more of the available signal identification methods can be used in a second phase according to the source determined in the first phase. In some cases one method alone may be used to obtain both types of information, e.g. using different ancillary codes for identical signals transmitted through different broadcast platforms or belonging to different regions. However, such approaches require the application of the different ancillary codes at the source of the broadcast transmission. Therefore, these single method prior art metering systems are not universally applicable for a range of broadcast devices and platforms. It follows that, according to most known-prior art metering systems, several signal identification methods need to be applied simultaneously in order to cover a variety of measurement cases, forcing the metering system to include a plurality of detection methods, increasing the probability of errors, malfunctions, and failures.
An example of an audience metering system that applies several different signal identification methods, and which is currently being used in many countries, is the TVM5 system, produced by AGB NMR Lab (see e.g., www.agblab.com).
In summary, the TVM 5 system can be used to monitor TV audiences of both analog and digital broadcasts. Furthermore, it contains features for measuring a plurality of different TV platforms and devices, to account for the new ways in which TV is being watched. In operation, the device can identify the active source on the screen using any of the magnetic field, electric field and the audio for analysis. The TVM 5 uses a total of seven methods to identify the channel being watched and/or the state or mode of peripheral devices to be measured in association with the TV. The channel identification process is performed in two phases, initially identifying the source of the transmission and then identifying the actual broadcast.
Yet another example of contemporary audience metering systems is the Telecontrol VIII produced by the Telecontrol Group. The Telecontrol VIII meter applies several different measuring methods dependent on the reception technology and particular equipment being used for any given household in which the audience measurement is being carried out. The Telecontrol VIII meter again needs to determine the source information though wired apparatus before it can decide how to identify the channel, or actual signal content.
Still another example of a metering system that requires wiring all peripherals to the metering device is the set-top version of the current UNITAM system (see e.g., www.unitam.tv). The UNITAM meter device includes several audio ports that must be connected to various media devices associated to the TV set under measurement. The UNITAM meter determines source information by comparing the signal received by its audio sensor with each of the signals available at the audio ports received through respective wires to determine the platform in use.
The UNITAM meter device has several ports to which media devices such as a DVD player, freeview box, digital or cable TV box, games console, or other media devices possibly associated with a TV set can be connected. During use, the meter detects the port from which the signal on the TV at any given time is coming from and begins to generate audio signatures from that port continuously as long as it remains active. When the current port becomes inactive, the UNITAM meter device must detect the port from which the signal is now being transmitted and begin to generate a different audio signature from that port continuously for as long as it remains active. These signatures are then processed in order to identify all the content shown on the associated TV set or display as coming from a particular platform or source. The UNITAM meter uses infrared logging as an auxiliary method for overcoming problems of simulcasting, wherein two or more TV stations transmit the same content at the same time.
It can thus be understood that many known metering concepts rely on wired connections between the TV set, one or more peripheral devices and the metering device in order to generate source information. This need for wired connection between several devices in metering device systems derives from the prior art approaches of identifying the source of a particular media broadcast and then deciding, based on that source information, what particular content identification method should be applied to identify the broadcast itself. The source and broadcast identification method used may include applying a code or tab to the broadcast transmission at the metering device via the wired connections to identify the different respective broadcast source devices. Thus known metering concepts are generally technically complex and, in some cases, require application of several different identification methods dependent on the source of a broadcast at any given time.